This container can be pulled via:
  docker pull registry.opensuse.org/home/dcassany/elementalnewdev/containers/rancher/seedimage-builder/5.3:1.2.5
  docker pull registry.opensuse.org/home/dcassany/elementalnewdev/containers/rancher/seedimage-builder/5.3:1.2.5-15.135
  docker pull registry.opensuse.org/home/dcassany/elementalnewdev/containers/rancher/seedimage-builder/5.3:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.